1. Field of the Invention
The present invention relates to a spindle motor and a hard disk drive including the same.
2. Description of the Related Art
A so-called shaft fixed type spindle motor may be mounted in an information recording and reproducing apparatus such as a hard disk drive, or the like, in which a shaft resistant to vibration is fixed to a case of a hard disk drive.
Namely, in order to prevent recorded information from being damaged and a state in which information cannot be written or read due to external vibrations developing, a spindle motor installed in a hard disk drive may employ a structure in which a shaft is fixedly installed.
Meanwhile, a spindle motor used in a hard disk drive is required to have a high degree of reliability, so it is necessary to maintain a quantity of a lubricating fluid provided in a fluid dynamic bearing assembly having a fixed shaft.
In a case in which a lubricating fluid is released from a liquid-vapor interface formed by the lubricating fluid and air and leaked outwardly, rotational characteristics of the spindle motor may be degraded and a rotating member and a fixed member forming a bearing clearance may be abraded due to a shortage of lubricating fluid.
Thus, the development of a structure capable of preventing leakage of a lubricating fluid outwardly and securing sufficient storage space for lubricating fluid is required.